c# - WPF 使用计时器重复一个 Action

Question

所以我是 WPF 的新手，我只是想制作一个简单的小程序。当您按下开始按钮时，它会不断打印假代码，直到您按下停止按钮。我试图让它重复，直到停止按钮被击中 10 种不同的方式，但它们都没有工作。 TextBlock 元素将更新一次(或永远不会)，然后整个程序变得不可用并且加载光标出现。我猜它不是经历一个循环，然后更新 TextBlocks，而是在后台执行所有操作，而不是进行视觉更新。

 public partial class MainWindow : Window
{
    System.Windows.Threading.DispatcherTimer dispatcherTimer = new System.Windows.Threading.DispatcherTimer();

    Random r1 = new Random();

    bool stop = false;
    int numUse

    public MainWindow()
    {
        InitializeComponent();


        dispatcherTimer.Interval = new TimeSpan(0, 0, 1);
        dispatcherTimer.Start();

    }

    //Executes when the start button is hit, begins timer
    private void Button_Click(object sender, RoutedEventArgs e)
    {
        do
        {
            dispatcherTimer.Tick += dispatcherTimer_Tick;
        } while (stop == false);
    }

    //Executes when the stop button is hit, ends timers do while loop
    private void Button_Click_1(object sender, RoutedEventArgs e)
    {
        stop = true;
    }

    private void dispatcherTimer_Tick(object sender, EventArgs e)
    {

            numUse = r1.Next(1, 2);

            if (numUse == 1)
            {
                CodeBlock1.Text = "struct group_info init_groups = { .usage = ATOMIC_INIT(2) }; ";
                CodeBlock2.Text = "";
                CodeBlock3.Text = "struct group_info *groups_alloc(int gidsetsize){ ";
                CodeBlock4.Text = "struct group_info *group_info; ";
                CodeBlock5.Text = "int nblocks; ";
                CodeBlock6.Text = "int i; ";
                CodeBlock7.Text = "";
                CodeBlock8.Text = "initialize stream";
            }
            else if (numUse == 2)
            {
                CodeBlock1.Text = "if (gidsetsize <= NGROUPS_SMALL) ";
                CodeBlock2.Text = "group_info->blocks[0] = group_info->small_block; ";
                CodeBlock3.Text = " else {  ";
                CodeBlock4.Text = " for (i = 0; i < nblocks; i++) { ";
                CodeBlock5.Text = "b = (void *)__get_free_page(GFP_USER);  ";
                CodeBlock6.Text = " goto out_undo_partial_alloc;  ";
                CodeBlock7.Text = "} ";
                CodeBlock8.Text = "";
            } else
            {

            }
    }



}

我试过 for 循环，do while，以不同的顺序使用不同的方法。我知道我在走那些路线时可能搞砸了，所以任何方法都适合我的目的。显然，在这种情况下我使用的是定时器。

Answer 1

不必在Button_Click的while循环中重复调用dispatcherTimer.Tick += dispatcherTimer_Tick。我怀疑当这个循环运行时，消息泵上的任何其他东西都不会运行，包括来自 DispatcherTimer 的滴答。

您可能可以取消 stop 并仅通过从代码中的任何位置调用 Stop() 直接对 DispatcherTimer 进行操作。

也许这样:

public MainWindow()
{
    InitializeComponent();


    dispatcherTimer.Interval = new TimeSpan(0, 0, 1);
    dispatcherTimer.Tick += dispatcherTimer_Tick; // set it up here

}

 //Executes when the start button is hit, begins timer
private void Button_Click(object sender, RoutedEventArgs e)
{
    dispatcherTimer.Start(); // start timer

}

//Executes when the stop button is hit, ends timers do while loop
private void Button_Click_1(object sender, RoutedEventArgs e)
{
    dispatcherTimer.Stop(); // stop timer
}